Optical Coherence Tomography News

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Barrett’s esophagus (BE) surveillance is limited by biopsy sampling error. Optical coherence tomography (OCT) enables microscopic resolution, high speed, volumetric imaging and is commercially available as volumetric laser endomicroscopy (VLE, NinePoint Medical). Studies investigated cross-sectional OCT dysplasia features, including a diagnostic algorithm (VLE-DA), however, many VLE studies used ex vivo specimens due to challenges in registering biopsy with OCT. We previously demonstrated ultrahigh-speed endoscopic OCT >10x faster than commercial instruments, enabling depth-resolved en face and cross-sectional imaging. This study investigated volumetric en face and cross-sectional OCT for identifying neoplasia. 74 OCT datasets with correlated biopsy/endoscopic mucosal resection histology (49 non-dysplastic BE (NDBE), 25 neoplasia) were obtained from 14 BE patients with history of dysplasia and 30 with NDBE in vivo. The associations between irregular mucosal patterns on en face OCT, and absence of mucosal layering, surface signal>subsurface, and >5 atypical glands on cross-sectional OCT versus histology and treatment history were assessed by 3 blinded readers. Atypical glands under irregular mucosal patterns occurred in 75% of neoplasia (96% of treatment-naïve neoplasia) versus 30% of NDBE datasets (43% of short and 18% of long-segment NDBE). Mucosal layering was absent in 35% of neoplasia and 53% of NDBE datasets, and surface signal>subsurface in 29% of neoplasia and 30% of NDBE datasets. Findings suggest that atypical glands under irregular mucosal patterns are associated with neoplasia and pathogenesis.

For more information see recent Article1, Article2, and Article3. Courtesy Osman O. Ahsen from the Massachusetts Institute of Technology. To share this article click Here.
Featured Articles
1. Hamamatsu develops bright supercontinuum source
  
  Explore optics.org Oct 16 2018 Other Business News , Broadband Sources
  
  Hamamatsu Photonics has developed a supercontinuum light source, also known the SC light source, that produces higher brightness – approximately 1000 times higher than the company’s own range of xenon lamps. At the same time, the SC source maintains the high stability equivalent to that of xenon lamps by optimizing output conditions and also using a high nonlinear optical fiber as its nonlinear optical material. This source is targeting the market for measuring the complex structure of semiconductor optical measurements. The company added that its official commercial release will be in the spring of 2019. The new SC light source ...
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2. Automated assessment of breast cancer margin in optical coherence tomography images via pre‐trained convolutional neural network
  
  Explore Wiley Online Library Oct 15 2018 Oncology
  
  The benchmark method for the evaluation of breast cancers involves microscopic testing of a hematoxylin and eosin (H&E) stained tissue biopsy. Resurgery is required in 20‐30% of cases because of incomplete excision of malignant tissues. Therefore, a more accurate method is required to detect the cancer margin to avoid the risk of recurrence. In the recent years, convolutional neural networks (CNNs) has achieved excellent performance in the field of medical images diagnosis. It automatically extracts the features from the images and classifies them. In the proposed study, we apply a pre‐trained Inception‐v3 CNN with reverse active ...
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  Mentions: UCLA
3. Quantitative Articular Cartilage Sub-Surface Defect Assessment Using Optical Coherence Tomography: An In-Vitro Study
  
  Explore ScienceDirect Oct 13 2018
  
  Assessment of structural cartilage damage is of high scientific and clinical interest. Optical Coherence Tomography (OCT) is a light-based cross-sectional imaging modality that allows the real-time assessment of articular cartilage at near-histological resolution. Algorithm routines for the detection, parameterization and quantification of sub-surface defects as assessed by OCT were implemented and validated in this study. Standard defects of 0.9 mm, 1.1 mm and 1.3 mm diameter were created in the sub-surface regions of macroscopically intact human articular cartilage samples (n = 60 defects of variable sizes in n = 20 samples). Subsequently, samples were scanned by 3D OCT and ...
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  Mentions: RWTH Aachen University Nicolai Brill Sven Nebelung
4. Interpretation of Optical Coherence Tomography Images for Breast Tissue Assessment
  
  Explore SAGE Journals Oct 13 2018 Oncology
  
  Purpose . Initial studies have shown that optical coherence tomography (OCT) is an effective margin-evaluation tool for breast-conserving surgery, but methods for the interpretation of breast OCT images have not been directly studied. In this work, breast pathologies were assessed with a handheld OCT probe. OCT images and corresponding histology were used to develop guidelines for the identification of breast tissue features in OCT images. Methods . Mastectomy and breast-conserving surgery specimens from 26 women were imaged with a handheld OCT probe. During standard pathology specimen dissection, representative 1-cm × 1-cm tissue regions were grossly identified, assessed with OCT, inked for orientation and ...
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  Mentions: Johns Hopkins University Diagnostic Photonics
5. Altris.AI – The New Era of Retinal Diagnosis is Coming
  
  Explore Optical Coherence Tomography News Oct 13 2018 Ophthalmology , Other Business News
  
  Altris.AI (Altris, Inc) announced it has signed an agreement with a South Korean ophthalmic and optical medical equipment manufacturer Huvitz Co., Ltd. aimed at the development of customized deep learning solutions for retinal diseases detection unique for Huvitz HOCT-1/1F device, All-in-One PC integrated 3D Optical Coherence Tomography (OCT) and Fundus Camera. Altris.AI’s OCT and Fundus algorithms have been trained using anonymized OCT retinal scans as well as Fundus images collected during more than 12 years, and are able to detect more than 50 retinal diseases and conditions. Currently, Altris.AI’s solution is available in web ...
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  Mentions: Huvitz
6. Post-doctoral Associate Position in Biophotonics / Biomedical Optical Imaging at Lehigh University
  
  Explore Optical Coherence Tomography News Oct 12 2018 Jobs & Studentships
  
  Position description: A full-time Postdoctoral Associate position in Biophotonics / Biomedical Optical Imaging is available at Lehigh University starting ASAP . The primary purpose of this position will be for a highly motivated individual to develop advanced optical imaging techniques for novel biomedical applications in vitro and/or in vivo . Compensation is commensurate with experience. Qualifications: Ph.D. in Electrical Engineering, Physics, Applied Physics, Biomedical Engineering / Bioengineering or related fields. Hands-on experience with optical coherence tomography (OCT), including spectral-domain and swept-source OCT, is preferred. Good publication record and communication skills. Research areas: The candidate is expected to work on one of the ...
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  Mentions: Massachusetts Institute of Technology National Institutes of Health James G. Fujimoto
7. Changes in volume of various retinal layers over time in early and intermediate age-related macular degeneration
  
  Explore Nature Publishing Group Oct 11 2018 Ophthalmology
  
  Purpose To evaluate longitudinally volume changes in inner and outer retinal layers in early and intermediate age-related macular degeneration (AMD) compared to healthy control eyes using optical coherence tomography (OCT). Methods 71 eyes with AMD and 31 control eyes were imaged at two time points: baseline and after 2 years. Automated OCT layer segmentation was performed using Orion TM . This software is able to measure volumes of retinal layers with distinct boundaries including Retinal Nerve Fibre Layer (RNFL), Ganglion Cell-Inner Plexiform Layer (GCIPL), Inner Nuclear Layer (INL), Outer Plexiform Layer (OPL), Outer Nuclear Layer (ONL), Photoreceptors (PR) and Retinal Pigment ...
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  Mentions: Jonathan D. Oakley Voxeleron
8. Non invasive optical cellular imaging in humans
  
  Explore Photonics Society of Poland Oct 6 2018
  
  One of the most appealing and still unsolved problems in biological and medical imaging is the possibility of noninvasive visualization of tissue in vivo with an accuracy of microscopic examination. A major difficulty to solve in biomedical imaging is a degradation of image quality caused by the presence of optical inhomogeneity of tissue. Is there any chance to develop a microscopic method that allows non-invasive observation of cells in living tissue? Classical optical microscopy requires first to retrieve, then to process and finally to stain the sample, which is usually not possible to be performed in vivo. One of the ...
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  Mentions: Maciej Wojtkowski Nicolaus Copernicus University
9. Advances in Optical Coherence Tomography
  
  Explore Photonics.com Oct 5 2018
  
  Optical coherence tomography (OCT) is a high-resolution, three-dimensional, noninvasive imaging technique. It is often called an optical ultrasound because it relies on time-of-flight information, similar to ultrasound imaging, to obtain subsurface information. The success of this technique has been fueled by a unique combination of technical and commercial factors, which include major investment in lasers, optical fibers, and sensors for telecommunications. That OCT is benefitting from these advances is proven in its applications across the health care industry. With close to a billion-dollar market size, OCT is seeing increased acceptance in areas such as interventional cardiology, dermatology, and ophthalmology, and ...
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  Mentions: Wasatch Photonics Nishant Mohan
10. Economical and compact briefcase spectral-domain optical coherence tomography system for primary care and point-of-care applications
  
  Explore SPIE Digital Library Oct 2 2018
  
  Development of low-cost and portable optical coherence tomography (OCT) systems is of global interest in the OCT research community. Such systems enable utility broadly throughout a clinical facility, or in remote areas that often lack clinical infrastructure. We report the development and validation of a low-cost, portable briefcase spectral-domain optical coherence tomography (SD-OCT) system for point-of-care diagnostics in primary care centers and/or in remote settings. The self-contained briefcase OCT contains all associated optical hardware, including light source, spectrometer, hand-held probe, and a laptop. Additionally, this system utilizes unique real-time mosaicking of surface video images that are synchronized with rapid ...
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  Mentions: Stephen A. Boppart University of Illinois at Urbana-Champaign Roshan Dsouza
11. Comprehensive intravascular imaging of atherosclerotic plaque in vivo using optical coherence tomography and fluorescence lifetime imaging
  
  Explore Nature Publishing Group Oct 2 2018 Cardiology
  
  Comprehensive imaging of both the structural and biochemical characteristics of atherosclerotic plaque is essential for the diagnosis and study of coronary artery disease because both a plaque’s morphology and its biochemical composition affect the level of risk it poses. Optical coherence tomography (OCT) and fluorescence lifetime imaging (FLIm) are promising optical imaging methods for characterizing coronary artery plaques morphologically and biochemically, respectively. In this study, we present a hybrid intravascular imaging device, including a custom-built OCT/FLIm system, a hybrid optical rotary joint, and an imaging catheter, to visualize the structure and biochemical composition of the plaque in an ...
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  Mentions: Wang Yuhl Oh Hanyang University Korea University
12. Assessment of Barrett’s esophagus and dysplasia with ultrahigh-speed volumetric en face and cross-sectional optical coherence tomography
  
  Explore thieme-connect.de Sep 30 2018 Gastroenterology
  
  Background This study aimed to evaluate the use of ultrahigh-speed volumetric en face and cross-sectional optical coherence tomography (OCT) with micromotor catheters for the in vivo assessment of Barrett’s esophagus and dysplasia. Methods 74 OCT datasets with correlated biopsy/endoscopic mucosal resection histology (49 nondysplastic Barrett’s esophagus [NDBE], 25 neoplasia) were obtained from 14 patients with Barrett’s esophagus and a history of dysplasia and 30 with NDBE. The associations between irregular mucosal patterns on en face OCT, absence of mucosal layering, surface signal > subsurface, and > 5 atypical glands on cross-sectional OCT vs. histology and treatment history were ...
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  Mentions: Massachusetts Institute of Technology James G. Fujimoto Thorlabs
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1. Phenotyping of Mouse Models with OCT
  
  Explore Home - Springer 20 hours, 42 min ago Ophthalmology
  
  Optical coherence tomography (OCT) is an invaluable technique to perform noninvasive retinal imaging in small animal models such as mice. It provides virtual cross sections that correlate well with histomorphometric data with the advantage that multiple iterative measurements can be acquired in timeline analyses to detect dynamic changes and reduce the number of animals needed per study.
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  Mentions: University of Tübingen
2. Retinal imaging with optical coherence tomography and low‐loss adaptive optics using a 2.8‐mm beam size
  
  Explore Wiley Online Library Oct 17 2018 Ophthalmology
  
  As data acquisition for retinal imaging with optical coherence tomography (OCT) becomes faster, efficient collection of photons becomes more important to maintain image quality. One approach is to use a larger aperture at the eye’s pupil to collect more photons that have been reflected from the retina. A 2.8‐mm beam diameter system with only 7 reflecting surfaces was developed for low‐loss retinal imaging. The larger beam size requires defocus and astigmatism correction, which was done in a closed loop adaptive optics method using a Shack‐Hartmann wavefront sensor and a deformable mirror with 140 actuators and ...
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  Mentions: University of Western Australia Barry Cense
3. Two-year outcomes of a pilot glaucoma suspect telemedicine monitoring program
  
  Explore Medical Journals Publisher Oct 17 2018 Ophthalmology
  
  Purpose: The purpose of this study was to characterize a pilot program using e-health to monitor glaucoma suspects in a large integrated health system. Methods: A retrospective chart review of patients enrolled in the first 2 years of a new glaucoma suspect telemedicine monitoring program was conducted. Patients were enrolled in the program after being diagnosed as glaucoma suspects in the regular clinic setting and were eligible for the program if they had better than 20/40 vision, intraocular pressure (IOP) <25 mmHg, a normal baseline visual field, and an optical coherence tomography (OCT) retinal nerve fiber layer (RNFL) without ...
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  Mentions: University of Michigan Tufts University
4. Next-level imaging puts optometry on front line of diabetes diagnosis
  
  Explore Healio.com Oct 16 2018 Ophthalmology
  
  Next-level imaging puts optometry on front line of diabetes diagnosis Primary Care Optometry News, October 2018 Add Emerging imaging technologies are improving evaluation, diagnosis and management of patients with diabetes and leading to earlier detection. These next-level technologies fall into three buckets: high-resolution, expanded field fundus photography; OCT angiography; and widefield imaging.
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  Mentions: Optovue Carl Zeiss Meditec FDA
5. Posterior Vitreous Structures Evaluated by Swept-source Optical Coherence Tomography with En Face Imaging
  
  Explore KoreaMed Synapse Oct 16 2018 Ophthalmology
  
  Purpose To evaluate posterior vitreous structures using swept-source (SS) optical coherence tomography (OCT) with en face imaging. Methods We retrospectively reviewed OCT images of healthy individuals who did not have intra-ocular disease. We obtained high-definition horizontal and vertical line scans crossing the fovea and 3D scans using SS-OCT, with the 3D scan centered between the fovea and the optic-nerve head. An enhanced vitreous visualization function was used to highlight vitreous structures. En face mode was used to measure the area of Martegiani (AM) and bursa premacularis (BP). We performed all measurements using a built-in function of the viewing software. Results ...
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6. Color Fundus Image Guided Artery-Vein Differentiation in Optical Coherence Tomography Angiography
  
  Explore IOVS Journal Oct 16 2018 Ophthalmology
  
  Purpose : This study aimed to develop a method for automated artery-vein classification in optical coherence tomography angiography (OCTA), and to verify that differential artery-vein analysis can improve the sensitivity of OCTA detection and staging of diabetic retinopathy (DR). Methods : For each patient, the color fundus image was used to guide the artery-vein differentiation in the OCTA image. Traditional mean blood vessel caliber (m-BVC) and mean blood vessel tortuosity (m-BVT) in OCTA images were quantified for control and DR groups. Artery BVC (a-BVC), vein BVC (v-BVC), artery BVT (a-BVT), and vein BVT (a-BVT) were calculated, and then the artery-vein ratio (AVR ...
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  Mentions: Xincheng Yao
7. Fusion of X-ray angiography and optical coherence tomography for coronary flow simulation
  
  Explore Leiden Repository Oct 16 2018 Cardiology , Student Theses
  
  In conclusion, this thesis proposes a new approach for reconstruction of coronary artery and the implanted BRS by fusion of OCT and X-ray angiography to analyze intracoronary ESS in vivo. The studies conducted in this thesis demonstrate the feasibility of the proposed approach to analyze the detailed local coronary hemodynamics in patients, including the SS patterns after BRS implantation in coronary bifurcations. We observed that in vivo assessment of ESS was closely related to: (1) reconstruction of the side branches; (2) reconstruction of the BRS; (3) patient-specific flow; (4) post-processing portion size in which ESS was calculated. Based on these ...
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  Mentions: Leiden University
8. Development of a full thickness macular hole after vitrectomy for rhegmatogenous retinal detachment: a sequential study via optical coherence tomography
  
  Explore BMC Ophthalmology Oct 16 2018 Ophthalmology
  
  Background To demonstrate a full thickness macular hole (MH) development after vitrectomy (VT) for rhegmatogenous retinal detachment (RRD) and to investigate the possible disease mechanism with optical coherence tomography (OCT). Case presentation A 47-year-old female underwent 23G vitrectomy surgery to repair the macula-detached RRD successfully. However, intraretinal cysts initially developed two months after surgery. Cysts gradually increased in number and size, and cystoid macular edema was noted at the 5th month. Thereafter, inner retina dehiscence and a lamellar macular hole developed. The lamellar hole further dehisced and progressed into a full-thickness MH at the 10th month. The patient then received ...
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9. Lens nuclear opacity quantitation with long-range swept-source optical coherence tomography: correlation to LOCS III and a Scheimpflug imaging-based grading system
  
  Explore BJO Online Oct 16 2018 Ophthalmology
  
  Purpose To quantitate lens nuclear opacity using long-range swept-source optical coherence tomography (SS-OCT) images and to evaluate the correlation of this method to Lens Opacities Classification System III (LOCS III) and a Scheimpflug imaging-based grading system (Pentacam Nuclear Stage function; PNS). Methods This study enrolled 120 participants (120 eyes) with age-related nuclear cataracts. The best-corrected visual acuity (BCVA), LOCS III nuclear opalescence (NO) and nuclear colour (NC) were obtained. The nuclear density measured using PNS function (ND PNS ) was recorded. Three successive series of long-range SS-OCT images were captured, and the nuclear region was analysed using ImageJ (NIH, Bethesda, Maryland ...
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  Mentions: National Institutes of Health Wenzhou Medical College
10. CHARACTERISTICS AND CLASSIFICATION OF TYPE 3 NEOVASCULARIZATION WITH B-SCAN FLOW OVERLAY AND EN FACE FLOW IMAGES OF OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY
  
  Explore LWW Online Oct 16 2018 Ophthalmology
  
  Purpose: To study B-scan flow overlay and en face flow optical coherence tomography angiography (OCT-A) images of Type 3 neovascularization (NV) and to characterize a staging system for Type 3 NV based on the OCT-A findings. Methods: We retrospectively collected data on consecutive treatment-naive eyes with Type 3 NV. All eyes underwent fluorescein angiography, indocyanine green angiography, structural spectral domain OCT, and OCT-A (AngioPlex). Localization and extension of abnormal flows detected by B-scan flow overlay and en face OCT-A images were assessed. Results: Of 24 eyes of 22 patients with Type 3 NV, B-scan flow overlay images showed that 4 ...
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  Mentions: Nagoya University
11. Is Optical Coherence Tomography a Potential Tool to Evaluate Marginal Adaptation of Class III/IV Composite Restorations In Vivo?
  
  Explore Operative Dentistry Oct 16 2018 Dentistry
  
  Objective: Margin analysis of Class III and IV composite restorations in vitro and in vivo occurred by scanning electron microscopy (SEM) and optical coherence tomography (OCT). The results were compared and related to clinical evaluation. Methods and Materials: Eight Class III composite restorations were imaged in vitro using OCT and SEM. The margins were analyzed quantitatively. OCT signals were verified by assignment to the criteria perfect margin, gap, and positive/negative ledge. In vivo quantitative margin analysis of Class III/IV composite restorations made of the micro-hybrid composite Venus combined with the self-etch adhesive iBond Gluma inside (1-SE) or etch-and-rinse ...
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  Mentions: University of Leipzig
12. Changes in Tear Meniscus Height Following Lower Blepharoplasty as Measured by Optical Coherence Tomography
  
  Explore KoreaMed Synapse Oct 16 2018 Ophthalmology
  
  Purpose The lower eyelid serves important roles in tear distribution and drainage. The purpose of this study was to measure the tear meniscus height (TMH) with anterior segment optical coherence tomography after lower blepharoplasty. Methods A total of 52 eyes from 26 patients treated between July 2012 and June 2015 were included in the study. A transcutaneous or transconjunctival approach was performed, depending on whether (1) the supportive lower lid orbicularis oculi muscle was tightened, (2) the middle lamella was elongated, (3) minimal fat was removed or transpositioned, and (4) lateral canthal support was established. Marginal reflex distance 2 and ...
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13. Preclinical quantitative in-vivo assessment of skin tissue vascularity in radiation-induced fibrosis with optical coherence tomography
  
  Explore SPIE Digital Library Oct 16 2018 Dermatology
  
  Radiation therapy (RT) is widely and effectively used for cancer treatment but can also cause deleterious side effects, such as a late-toxicity complication called radiation-induced fibrosis (RIF). Accurate diagnosis of RIF requires analysis of histological sections to assess extracellular matrix infiltration. This is invasive, prone to sampling limitations, and thus rarely used; instead, current practice relies on subjective clinical surrogates, including visual observation, palpation, and patient symptomatology questionnaires. This preclinical study demonstrates that functional optical coherence tomography (OCT) is a useful tool for objective noninvasive in-vivo assessment and quantification of fibrosis-associated microvascular changes in tissue. Data were collected from murine ...
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  Mentions: University of Toronto I. Alex Vitkin Costel Flueraru
14. Automated identification of cone photoreceptors in adaptive optics optical coherence tomography images using transfer learning
  
  Explore OSA | OSA Publishing Oct 16 2018 Ophthalmology
  
  Automated measurements of the human cone mosaic requires the identification of individual cone photoreceptors. The current gold standard, manual labeling, is a tedious process and can not be done in a clinically useful timeframe. As such, we present an automated algorithm for identifying cone photoreceptors in adaptive optics optical coherence tomography (AO-OCT) images. Our approach fine-tunes a pre-trained convolutional neural network originally trained on AO scanning laser ophthalmoscope (AO-SLO) images, to work on previously unseen data from a different imaging modality. On average, the automated method correctly identified 94% of manually labeled cones when compared to manual raters, from twenty ...
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  Mentions: University of British Columbia Marinko V. Sarunic Simon Fraser University
15. OPTICAL COHERENCE TOMOGRAPHY BIOMARKERS TO DISTINGUISH DIABETIC MACULAR EDEMA FROM PSEUDOPHAKIC CYSTOID MACULAR EDEMA USING MACHINE LEARNING ALGORITHMS
  
  Explore LWW Online Oct 16 2018 Ophthalmology
  
  Purpose: In diabetic patients presenting with macular edema (ME) shortly after cataract surgery, identifying the underlying pathology can be challenging and influence management. Our aim was to develop a simple clinical classifier able to confirm a diabetic etiology using few spectral domain optical coherence tomography parameters. Methods: We analyzed spectral domain optical coherence tomography data of 153 patients with either pseudophakic cystoid ME (n = 57), diabetic ME (n = 86), or “mixed” (n = 10). We used advanced machine learning algorithms to develop a predictive classifier using the smallest number of parameters. Results: Most differentiating were the existence of hard exudates, hyperreflective ...
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